Multi-Tab JSON Editor
Edit multiple JSON files in tabs.
About the Multi-Tab JSON Editor
Work on several JSON documents at once without juggling browser windows. Each tab holds its own input and output, and your tabs are saved in this browser so they are still there when you come back.
- Click + in the tab bar to open a new tab. Click a tab to switch to it, or × to close it.
- Paste or type JSON into the Input JSON pane of the active tab.
- Click Format to pretty-print the input into the Output pane, or Minify to compact it onto one line.
- Switch tabs freely - each tab keeps its own input and output, and nothing is lost when you move between them.
- Tabs are saved to your browser's local storage automatically, so a page refresh or a closed tab doesn't lose your work.
- The Output pane is editable too. Use it to keep notes, an expected result, or a second version of the document next to the original.
- Indentation follows your editor settings, so formatted output matches the style your project uses.
Why edit JSON in tabs?
Real work rarely involves a single JSON file. You compare a request with its response, keep a staging config next to a production one, or collect API samples while debugging. A multi-tab JSON editor keeps all of those documents open side by side in one place, instead of spread across text editors and browser windows.
What each tab gives you
- Its own input and output. Format or minify one document without touching the others.
- Syntax highlighting and error detection from the same code editor used across JSONEdit.
- Automatic saving. Tabs and the active tab are restored the next time you open the page in this browser.
- Private by design. Content stays on your device - nothing is uploaded to a server.
Common uses
- Keeping an API request body in one tab and the response in another while debugging an endpoint.
- Holding development, staging and production versions of a config file side by side.
- Collecting sample payloads (webhooks, events, fixtures) before writing tests or documentation.
- Cleaning up several minified API responses in one session, one tab per response.
Frequently asked questions
Where are my tabs stored?
In your browser's local storage on this device. They are not uploaded anywhere, so they won't appear on another computer or browser, and clearing your site data removes them.
Is there a limit on the number of tabs?
There is no fixed limit. Browsers do cap local storage (typically around 5 MB per site), so very large documents across many tabs may stop being saved. For a single large file, the JSON Editor is a better fit.
How do I see the differences between two tabs?
Copy the two documents into Compare JSON. It runs a structural diff and lists added, removed and changed values.
What happens if a tab contains invalid JSON?
Format and Minify need valid JSON, so you'll see an error instead of output. The editor marks the problem line. Common JSON Errors explains how to fix the usual causes, such as trailing commas and single quotes.